Infusion package with expandible bottom and method of manufacture thereof



Oct. 1951 H. o. IRMSCHER INFUSION PACKAGE WITH EXPANDABLE BOTTOM ANDMETHOD OF MANUFACTURE THEREOF Filed Oct. 24, 1949 ON Q INVENTOR. Hfi/vs0. JRMSO/ER Patented Oct. 16, 1951 INFUSION PACKAGE WITH EXPANDIBLEBOTTOM AND METHOD OF-MANUFAC- TURE THEREOF Hans 0. Irmscher, EastHempstead, N. Y., assignor to National Urn Bag Co. Inc., a corporationof New York Application October 24, 1949; Serial No. 123,145

9 Claims. 1

This invention relates to an infusion package manufacture and moreparticularly is directed to an improved expandable construction ofinfusion packages such as incorporated in tea balls and the likearticles, and to a novel method of producing same economically.

Among the objects of the invention is to provide infusion packages asinexpensive articles of manufacture, which shall be capable of quantityproduction on automatic high-speed packaging machines, which shall havejoint seams retain against separation by suitable adhesive means, suchfor example, as by a heat sealing process to provide an improved form oftea bag having a minimum of foreign matter and normally of smalleconomical size capable of expanding during a brewing operation todiminish the time for brewing relative to that required when otherwiseconstructed, and which construction and a method of manufacture thereofshall be practical and efficient to a high degree in use.

Other objects of the invention will in part be obvious and in parthereinafter pointed out. The invention accordingly consists of featureof construction and method of combination elements, arrangement of partsand steps in the process of manufacture which will be exemplified in theconstruction and method hereinafter described, and of which the scope ofapplication will be indicated in the following claims.

Fig. 1 is a side elevational view of a manufacturing layout, partlydiagrammatic, showing steps in producing infusion packages each with aninfolded expandable bottom in the form of an inverted pleat embodyingthe invention.

Figs. 2, 3 and 4 are cross-sectional views taken on lines 22, 3-3 and4-4, respectively, in Fig. 1 showing the web folding in successivephases in forming the improved infolded expandable bottoms of thetea-balls body portions in practing the improved method.

Fig. 5 is a front elevational view of an improved tea ball manufacturedto embody the invention with an inverted pleat expandable bottomconstruction as supplied in packaging and and distribution before using.

Fig. 6 is a bottom plan view of the improved tea ball shown in Fig. 5.

Fig. 7 is a cross-sectional view taken on line 'I'! in Fig. 5, showingdetails of the inverted pleated expandable bottom construction.

Fig. 8 is a fragmentary perspective view of the improved tea-ball shownin Fig. 5 showing the exterior region of the corner formed between theside or transverse edge seam joint and said inverted pleat bottomstructure before expansron.

Fig. 9 is a fragmentary perspective view corresponding to Fig. 8 butshowing the side or transverse edge seam joint and. the bottom cornerregion expanded during the brewing operation, and

Fig. 10 is a cross-sectional view taken on line ltlil in Fig. 9 showingsaid inverted pleat expanded bottom construction during the brewingoperation.

Referring in. detail to the drawing 2i] denotes an improved constructionof an infusion package in the form of a square pillow-shaped tea ballmanufactured to embody the invention.

As seen from Figs. 5, 6 and 7, tea ball 20 may comprise a bag portion200 made of a strip of filter sheet material 2i folded over on itself,and provided with an expandable bottom, that is, creased edge portions22 forming between superimposed layers of overlying flattened exteriorsides 20?) of tea ball 20. Exterior sides 202; are adhesively secured onthe remaining three edge portions of the margin areas thereof at sideedge border joint seams or flanges 23 and 2-4, and top edge border jointseam 25 to completely seal the tea-ball bag 20a which is partiallyfilled with.

essence containing product, as for example, tea T, forming the contentsthereof.

The strip of filter sheet material 21 may be supplied from a suitablesource in the form of a web of the required width, a sufiicient lengthof the web being cut and folded and creased to form the tea bag 20a, orif desired precut strips of sheet material 2! of proper shape and lengthmay form .such supply source (not shown).

Sheet material 2| may be of foraminous, as for example, filter paper,finely perforated parchment paper or cellophane, cotton gauze or thelike. Sheet material 2i used in the practicing of the invention heredescribed has a filter paper base layer 2 I a coated on one side with apreconditioned 'thermosetting plastic lamina? lb of a character such asdescribed in Menzel Patent No. 2,306,400, granted December 29, 1942, orother similar suitable filter sheet base layer coated with thermosettingplastic lamina for forming said heat sealed border joint seams orflanges 23, 24 and 25 in the manner hereinafter more fully described.

A suitable filter paper sheet forming base layer Zla may be made ofvegetable fibrous pulp stock, said layer 21a with thermosetting coatingof lamina '2lb being such that when made into the tea-ball bag portion20a, the latter has sufficient wet strength to withstand immersion inboilin water without damage or distintegration and without undue loss oftensile strength. The filtering sheet material 2| comprising the layer 2la and coating 2|b when forming the tea-ball bag portions 20a must besuch as to permit ready infusion, that is, rapid circulating passagetherethrough of the water of immersion for brewing and straining thefiller or tea contents T, said layer 2|a, coating 2|b and flanges 23, 24and 25 as copolymer of vinyl chloride and vinyl acetate uniformly spreadon one side thereof in an adhering dry state provides a satisfactory,pervious coating or lamina 2|b which does not materially affect thefiltering capacity of the layer 2|a. Approximately three ounces of suchvinyl resin when used for each pound of said layer 2 |a. will form saidcoating or lamina 2 lb of normally less than .0005 inch thick.

Sheet material 2| after taken from a supply source such as roll R, maybe made into the teaball bags portions 20a and filled with the contents,T, the tea-ball bag portions 20a, each having the coating 2 lb of thesheet material 2| positioned on interior surfaces thereof so that theborder edge joint seams or flanges 23, 24 and 25 are sealed on placingthe coating portion 2|b thereof in face to face relation and applyingpressure and heat to a fusion temperature by suitable clamping means ofany well known construction. With the coating or lamina 2|b formed of aconditioned vinyl resin permanent sealing fusion will take place whenpressure and heat of approximately 130 C. is applied.

. Since it has been found highly desirable to 'use a minimum of foreignmaterial in making up infusion packages such as tea balls 20, so as toeliminate possible contaminations that might affect the flavor of thebrew, each bag portion 20a is made as small in dimensions as possible torequire the least amount of filter sheet material 2| for obtaining asatisfactory brew from a predetermined contents T. Such prescribed sizeof bag portion 20a. also results in economy of material, group packagingand transportation. Furthermore, it has also often been found adinfoldas in inverted pleat 22a which is normally concealed within the bagportion 20a as shown in Figs. 5 and 8. Said body portion 20a is soconstructed and arranged that when it is immersed in or subject to theaction of boiling water the inverted pleat 22a automatically'unfolds toimmediately present and make fully available increased filter surfacesat said expandable bottom 22 which also allows for expansion of the teacontents T during the brewing operation yet said tea balls 20 can bemade most economically in quantity production at extremely high manu- 4facturing speed requiring a minimum of material and labor.

In the manufacturing of infusion packages such as tea-balls 20 and thelike, there is provided some form of string-handle 26 to manipulate thetea-ball 20 during the brewing operation which may be carried out in adrinking vessel, such as a cup, and also a tag 21 which may bear alegend such as the name or trade-mark of the manufacturer, grade of tea,etc. Such stringhandles 26 may each be attached to the tea-ball bag 20ain any suitable manner, and the free end 26a of the string handle 26terminated by the tag 21.

- Bag portions 20a after being filled with the contents T, have top edgeand side border joint seams 25, 24 and 23 heat sealed and each bagportion 20a then provided with string-hand1e 26 which may be anchored byone end 26b thereof, opposite said free end 26a, through suitable means,such as a staple 28 to the top edge border joint seam 25 which as seenin the completely manufactured tea ball 20 in Fig. 5 to extend along atop edge of bag portion 20a opposite said expandable bottom 22.

As is clear from Figs. 6 to 10, the side edge border joint seams orflanges 23 and 24, each having relatively short branches 23a, 23b and24a, 24b, respectively, extend into opposite corner regions of bagportion 20a which regions are formed by said branches 23a, 23b, and bybranches 24a and 24b at opposite ends of expandable bottom 22, so that,when tea ball 20 is first immersed into water for brewing, invertedpleat 22a, forming said bottom 22, in expansion,

automatically unfolds from the manufactured position shown in Figs. 5, 6and 8, with corner regions and said branches 23a, 23b and 24a, 24bcollapsed, that is, in abutment aligning with said joint seam or flange23, and 24, respectively, to expand for brewing operation as shown inFig. 9

with said joint seam branches 23a, 23b and 24a,

24b at said corner region unfolded and re-formed with respect to saidjoint seam or flange 23 and 24, respectively, as an inverted flattenedY- shaped structure.

Thus tea bag 20a is self-transformed from the manufactured pillow shapewith crimped side edge flanges 23 and 24, infolded bottom 22 andcollapsed crimped branches 23a, 23b and 24a and 24b shown in Figs. 5, 6,7 and 8 to the improved brewing box-like bottom structure shown in Figs.9 and 10.

The top edge border joint seam 25 of bag portion 20a may be constructedin the same manner as described in my Patent No. 2,458,169 issuedJanuary 4, 1949, said top seam joint 25 having unsealed extreme edges25a of unbroken length extending from side edge seam joint 23 to sideedge seam joint 24 and extending in width beyond the top joint seam 25 asuflicient distance to retain a flow of the heat sealing material frompassing beyond said extreme edges 25a during fusion, said unsealed edges25a being kept substantially free from heat sealing material to preventfouling heat sealing means such as used in high-speed manufacturing oftea-balls 20.

In the tea ball making art, method of manufacture to have commercialutility must be readily adapted for incorporation in the operation ofsuper and high-speed automatic machinery, so that low cost large scaleproduction is made possible. It is contemplated to practice the improvedmethod embodyin the invention to include in the manufacturing operationthe novel step of forming of said creased edge portions or expandable 5.bottom 22 infolded as an inverted pleat 22d which is normally concealedwithin the bag per: tion a as shown in Figs. 5, 6, 7 and 8. Suitablemeans for providing this additional step in the manufacture can bereadily incorporated in pres= ent high and super high speed automaticmachines of various types without extensive changes, and as here shownin Fig. 1 is incorporated in a super high-speed type such as is fullydisclosed in my Patent No. 2,475,617, issued July 12, 1947, formanufacturing of tea ball 20. i

The manufacturing layout shown in Fig. 1, which is partly diagrammatic,has saidweb of heat sealing filter paper sheet 2! continuously fed fromthe roll R and is longitudinally flexed by folder F, so that coating orlamina 21-17 of the flexed web sheet 2| is positioned to form the interior surfaces of tea bags 20a, and the border edges joint seams 23, 24and 25, for presenting said lamina 2 lb in a face to face relation forpressure heat sealing. Simultaneously the web former F infolds saidexpandable inverted pleat 22a in said fold bottom 22. Said web sheet 2|thus flexed and folded is gripped transversely the length thereofbetween continuously moving pairs of closely spaced pincer jaws G.

Said jaws G are carried on endless chain belt Z and are controlled foreffective opening and closing b suitable camming action of rollers Driding on rails E. Each jaw G is made U-shaped to grip the folded stripweb sheet 2i transversely to form successive empty bag sections of saidmoving strip web sheet 2|. Each bag section thus formed extends betweenforked portions of the jaws G leaving top edges of the bag sections opento project above the level of said jaws G.

As the empty bag sections continuously advance they are filled with ameasured quantity of infusion product, such as tea leaves T, whichduring part of said advance movement flow into said bag sections topopenings from a, suitable charging mechanism (not shown) in the wellunderstood manner, through moving funnels C that pass in and out of thebag sections and around in a closed path in timed relation with fillingoperation as fully described and shown in my said Patent No. 2,475,617.After each filling operation the top openings and transversely extendingside closures between the adjoining filled bag sections are heat-sealedto form said crimped joint seams 25, and 24, 23', respectively, inmultiple by pressure electric heated dies H provided for that purpose.Filled bag sections permanently heat sealed are then cut apart bysuitable shearing means, such as knives K, to form individual filled teabag portions 20a which continue uninterruptedly to advance.

Just after the knives K have been effective to leave, individual tea bagportions 20a, each between a pair of jaws G, a tag forming and stringhandle supply means automatically cooperates in time sequence with theadvancing movement of the bag portions 20a to supply each with a stringhandle 26 and tag 27 and to anchor the same by staple 28 to the top edgejoint seam 25. Such automatic cooperating tag forming and string handleapplying means is fully described and shown in my copending applicationSer. No. 79,034, filed March 1, 1949, for the manufacture of packageswith string handles. 1

Thus in practising the invention, improved steps of manufacture areprovided in which a part of the bottom 22 throughout the length thereofis simultaneously re-formed during the bottom inverted pleat foldingoperation to temporarily collapse the package structure so as to providefor automatical unfolded expansion during the in'fu sion operation, orfolding the moving web with a closed invertedly pleated bottom and heatsealing the transversely extending portions of the coated web to formside edge joint seams with temporarily abutting branches for expandingthe pleated bottom throughout the length thereof during infusionoperation.

It is thus seen, therefore, that there is provided an improved method ofoperation and article in which the objects of the invention are achievedand which are well adapted to meet all conditions of practical use.

As various possible embodiments may be made in the above invention foruse for different purposes and as various changes might be made in thearticle embodiment and method above set forth, it is understood that allthe above matters here set forth or shown in the accompanying drawingare to be interpreted as illustrative and not in a limiting sense. 7

I claim:

1. In an infusion package body portion construction of the characterdescribed having heat-sealed top and side edge joint seams provided witha suspension string handle anchored on a midportion of said top seamjoint, a crease folded bottom opposite said top seam joint fer said bodyportion manufacturedwith an inverted pleat expandable along the entirelength thereof, the side edge joint seams normally having collapsedbranches in aligned abutment terminating said pleat for automaticallyunfolding during infusion operation of said package body portionconstruction when suspended by the string handle to re-form said creasefolded" bottom in making an expanded structure thereof with saidbranches moved out of said aligned abutment.

2. In an infusion package body portion construction of the characterdescribed having heatsealed side edge joint seams and a top closurejoint, a suspension string handle anchored to a midportion of saidtopclosure joint, a creasefolded' bottom opposite said top closure marinfacturedwith an inverted pleat expandable along the entire lengththereof, the side edge joint seams normally having collapsed branches inaligned abutment terminating ends of said crease-folded bottomconstructed and arranged to automatically unfold during an infusionoperation when suspended by the string-handle for re-forming saidcrease-folded bottom to expand the structure thereof with the branchesof each joint seam separated from said aligned abutment to a relativelyinverted Y-formation.

3. An infusion package of the character described comprising an essencefilled rectangular-shaped bag portion formed of filter paper having athermo-plastic coating on one surface thereof folded over on itself withsaid coating in face to face relation, a creased bottom formed in saidfolded over bag portion with an expandable open-ended inverted pleat,portions of the coating at sides and top edge border of the bag portionbeing heat and pressure sealed to form side edge joint seams and topclosure for enclosing the filled essence in the bag portion, said sideedge joint seams when manufactured having extension branches borderingsaid open ended invertedpleat in temporary abutment alignment ofcollapsed construction at opposite corners of said creased bottom whichsaid extension branches during brewing operation of the essenceself-transform from a pillow shape bag portion to unfold said invertedpleat for'providing a boxlike expanded bottom structure for said bagportion with said joint seam extension branches separating out of saidalignment.

4. An infusion package comprising an essence filled bag portion formedof filter paper having a thermo-plastic coating on one surface thereoffolded-over on itself with said coating in a face to face relation, acreased bottom between said folded-over portion forming an expandableopenended inverted pleat, heat sealed joint seams formed with portionsof the coating at the sides and top edge border of the bag portion forenclosing the filled essence therein, said edge joints having extensionbranches bordering an openended inverted pleat normally in temporaryabutment of a collapsed construction at opposite corners of said creasedbottom which said extension branches self-transform during infusionoperation by unfolding said pleat to assume a relatively invertedY-formation, and a string-handle anchored to a midportion of the topedge border joint seam opposite said pleated bottom.

5. In an infusion package construction, a pillow-shaped bag portionformed of a filter paper sheet having a thermo-plastic coating on onesurface thereof folded-over on itself with said coating in face to facerelation, heat-sealed joint seam produced with said coating forenclosing an essence product in said bag portion, and an openendedinverted pleat formed in said folded-over portion of said sheet toprovide a bottom automatically expandable the entire length thereofduring infusion operation of said essence in the bag portion.

6. In a method of manufacturing rectangularshaped infusion packages eachhaving a suspension string-handle and an expandable bottom opposite saidhandle in a continuous unbroken sequence, the steps of folding a movingweb of filter paper having a porous thermo-plastic sealing coatinglengthwise with a closed bottom and open top and simultaneously invertpleating a part of i said bottom for forming a collapsed constructionthereof, temporarily retaining spaced predetermined portions transverseof the folded and pleated web to provide package body sections,

moving charges of an infusion product in the path 50 of movement of saidsections, filling said sections with said charges While being moved,heat and pressure sealing said top and temporarily retained transverseportions to provide permanent closure joint seams, successively severingthe leading filled package section to provide individual sealed packagebodies, and anchoring a string handle midway the top seam joint closureopposite said pleated bottom with said pleated bottom preconditioned toautomatically re-form from said collapsed construction for expansionduring infusion operation.

7. In a method of manufacturing infusion packages of the characterdescribed, the steps of folding a moving web of filter paper having aporous thermo-plastic sealing coating lengthwise to provide a closedbottom and open top, and simultaneously re-forming a part of said bottomthroughout length thereof to temporarily collapse the package bottomstructure for automatically unfolded expansion during infusionoperation.

8. In a method of manufacturing infusion packages of the characterdescribed, the steps of folding a moving web of filter paper having aporous thermo-plastic sealing coating lengthwise to provide a closedinvertedly pleated bottom, and heat sealing spaced transverselyextending portion of said coated web to form side edge joint seams withtemporarily abutting branches of each package for expanding the pleatedbottom throughout the length thereof during infusion operation.

9. In the method of manufacturing infusion packages of the characterdescribed, the steps of folding a continuously moving web of filterpaper having a porous thermo-plastic sealing coating lengthwise toprovide a closed bottom and open top and simultaneously re-forming apart of said bottom throughout the length thereof with an invertedpleat, and heat sealing spaced transversely extending portion of thecoated web to form side edge joint seams with temporarily abuttingbranches of each package for expanding the pleated bottom throughout thelength thereof during infusion operation.

HANS O. IRMSCHER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,186,087 Yates Jan. 9, 19402,306,399 Menzel Dec. 29, 1942

1. IN AN INFUSION PACKAGE BODY PORTION CONSTRUCTION OF THE CHARACTERDESCRIBED HAVING HEAT-SEALED TOP AND SIDE EDGE JOINT SEAMS PROVIDED WITHA SUSPENSION STRING HANDLE ANCHORED ON A MIDPORTION OF SAID TOP SEAMJOINT, A CREASEFOLDED BOTTOM OPPOSITE SAID TOP SEAM JOINT FOR SAID BODYPORTION MANUFACTURED WITH AN INVERTED PLEAT EXPANDABLE ALONG THE ENTIRELENGTH THEREOF THE SIDE EDGE JOINT SEAMS NORMALLY HAVING COLLAPSEDBRANCHES IN ALIGNED ABUTMENT TERMINATING SAID PLEAT FOR AUTOMATICALLYUNFOLDING DURING INFUSION OPERATION OF SAID PCKAGE BODY PORTIONCONSTRUCTION WHEN SUSPENDED BY THE STRING HANDLE TO RE-FORM SAID CREASEFOLDED BOTTOM IN MAKING AN EXPANDED STRUCTURE THEREOF WITH SAID BRANCHESMOVED OUT OF SAID ALIGNED ABUTMENT.